This application claims the benefit of International Application No. PCT/CN00/00136, filed Jun. 2, 2000, which claims benefit of Chinese Application No. 00216141.9, filed Jan. 12, 2000, which status is pending.
The present invention relates to a vacuum cleaner, especially to an telescopic dust-collecting pipe for vacuum cleaner.
The known technology, such as EP0293518, has disclosed a dust collecting pipe of vacuum cleaner, including inner pipe, outer pipe and locking mechanism. While pushing the button of said locking mechanism in one direction, locking mechanism could be released, and inner pipe could be extended or contracted relative to outer pipe. However, the button could be pushed only in one direction to release the locking mechanism, while extending and contracting the dust-collecting pipe, the directions of the force applied on dust-collecting pipe are opposite. Therefore, the directions of force applied on button and on dust collecting pipe with same hand may be right opposite and it is inconvenient for operating.
One object of the invention is to provide an telescopic pipe which may have locking mechanism with double direction of operating. So as to achieve the applying force direction of operating locking mechanism to be released may be the same as the applying force directions of operating dust collecting pipe extending and contracting. It is more convenient to operate dust-collecting pipe to be extended and contracted.
The technical scheme of the invention is in that an telescopic dust collecting pipe for vacuum cleaner includes outer pipe, inner pipe inserted in the outer pipe and locking mechanism used for locking relative position of inner pipe and outer pipe. The characteristic is in that the oriented groove is arranged axially at intervals on outer surface of said inner pipe. Controlling rod is provided slidingly in inner pipe, oriented groove corresponding to the oriented groove on inner pipe is arranged at same intervals on the controlling rod to form outer layer oriented groove and inner layer oriented groove. The relative movement between controlling rod and inner pipe causes outer layer oriented groove to coincide or stagger with inner layer oriented groove. Locking element movable along axial direction is arranged between outer pipe and inner pipe, the locking element is pressed against one side of inner pipe by elastic element. While two layers of oriented groove are coincided, the locking element is pressed into the oriented grooves coincided, outer pipe and inner pipe are locked relatively. While two layers of oriented groove are staggered, locking element is pushed out of oriented groove, locking condition between outer pipe and inner pipe is released.
The present invention utilizes a two layers structure of oriented groove. Therefore, double directional relative movement back and forth between controlling rod and inner pipe can bring outer layer oriented groove to stagger with inner layer oriented groove. And during the movement of staggering, locking element is pushed up by using the groove wall of inner layer oriented groove so as to release locking device. Such that the direction of releasing locking movement of double direction is the same as the direction of extending and contracting movement of double direction of dust collecting pipe. Therefore, during pushing and pulling in the invention, the direction of applying force acted on operating device with one hand may be same as the direction of pulling and pushing dust-collecting pipe so as to achieve the object of convenient operation.